This invention relates to bearing lubrication systems and, more particularly, to bearing lubrication systems for conveyor idler roll assemblies wherein a roll element is mounted on bearings to rotate with respect to its mounting shaft or spindle.
Properly maintained bulk conveyor idler rolls often last 20 years or more. The service life of a roll usually depends upon the life of the antifriction bearing mounting the roll on its shaft. Bearing life may sometimes be increased by relubrication, since relubrication replenishes lubricant available to the bearing and purges contaminants from the bearing area by the introduction of fresh, clean lubricating grease.
To ensure that all bearings are relubricated, it is desirable to grease each bearing individually. While individual bearing greasing operations are possible, at least on one side of flat return and conveying idler roll assemblies, the configuration of troughing idler roll assemblies limits direct accessibility to the two outside bearings on the idler roll wings only, and often the conveyor structure provides access to only one side of the conveyor so that only one bearing area can be reached for lubrication.
Thus, in a typical troughing idler assembly, the trough is formed by a horizontal idler roll and two inclined wing idler rolls so that the assembly includes six bearings. Therefore, two of the bearings are directly accessible and, in some cases, only one of the bearings on one side of the conveyor can be reached.
In order to eliminate the problem of access to lubrication fittings, idler rolls have been designed so that direct access is provided to each bearing to be lubricated by tubing and the tubes lead from each bearing to a convenient access station at one side of the conveyor. In this instance, six fittings would be arranged in a group for access. The additional lube lines add significant additional cost to a high volume competitive product, and the user often views the number of fittings to be indicative of his lubrication maintenance cost.